Field of the Invention
The present invention relates to an imaging device and an imaging system.
Description of the Related Art
Japanese Patent Application Laid-open No. 2013-211833 discloses a technique of increasing the speed in an imaging device having a plurality of pixels each of which includes a plurality of photoelectric conversion units. Each of the plurality of pixels included in the imaging device outputs a ranging signal that is based on signal charges of a part of the plurality of photoelectric conversion units and an image signal that is based on signal charges of the plurality of photoelectric conversion units. Further, Japanese Patent Application Laid-open No. 2013-211833 also discloses an imaging device that adds ranging signals of a plurality of pixels and outputs the added ranging signals.
Further, Japanese Patent Application Laid-open No. 2014-106478 discloses detecting saturation of a signal that is based on charges of a part of the plurality of photoelectric conversion units included in a pixel and detecting saturation of a signal that is based on charges of other photoelectric conversion units.
In an imaging device that adds ranging signals of a plurality of pixels and outputs the added ranging signals, however, an error may occur in ranging information when there is saturation in at least one of the plurality of ranging signals to be added. This may cause an error in a process in an imaging system on which the imaging device is mounted.